The inability of reconnaissance to distinguish between friend or foe in low light or total darkness is a major failing of battlefield and law enforcement operations. In these types of lighting conditions, not only does the probability of fratricide (the inadvertent killing of friendly forces by other friendly forces) increase, but time and resources are wasted during attempts to confirm identification. Furthermore, during the heat of battle, mistakes in identification are more likely to occur. Accordingly, there is a need to facilitate effortless and accurate nighttime identification and classification of a distant target or location by a remote sensor.
To this end, beacons have been used in conjunction with night vision equipment including light-intensifying systems that operate by amplifying visible and near infrared light. Beacons emit unique flashing infrared or thermal signatures referred to as signaling programs that are distinguished from operational surroundings by means of intense concentrated energy pulses. Although invisible to the naked eye, signaling programs emitted by beacons can be seen through fog, smoke, and darkness when viewed through night vision or thermal imaging (FLIR) observation devices.
Beacons are generally carried by soldiers and law enforcement personnel. Accordingly, beacons need to be lightweight. Further, since soldiers and law enforcement personnel often carry beacons in the field, beacons need to be powered by readily-available power sources that can be easily procured and replaced. Beacons powered by readily-available, small sources would meet both these weight and availability requirements. Using a commercially available, small source to power a beacon, however, presents circuit design challenges because the voltage output of these power sources is generally lower than the operating voltage of the elements being driven by the power source. For example, these power sources may drive emitters such as thermal or infrared light emitting diodes or thermal solid state devices having an operating voltage that exceeds the nominal characteristics of the power source.